table {
    border: 1px solid rgb(222, 226, 230);
    border-collapse: collapse;
}
th,td {

    border: 2px solid rgb(222, 226, 230);
    /*为单元格单独设置边框*/
    text-align: center;
}
tr:hover{
    /* background-color: rgb(236, 236, 236); */
    box-shadow: 5px 10px 5px 3px rgba(0,0,0,0.5);
    transform: translateY(-3px);
}
tr:nth-child(even) {
    background-color: rgb(236, 236, 236);
}
.one {
    width: 60px;
    height: 45px;
}
.two {
    width: 100px;
    height: 45px;
}
.three {
    width: 400px;
    height: 45px;
}

body {
    background-image: url("../img/tree.png");
    background-repeat: no-repeat;
}

.main {
    text-align: center;
    background-color: white;
    width: 572px;
    height: auto;
    margin: auto;
}